A basic input/output system (BIOS) is a firmware that ensures a system's computing components are functional. The BIOS stores firmware that is executed when the computer system is first powered on, along with a set of configurations specified for the BIOS. The BIOS typically recognizes, initializes, and tests hardware in a computing system.
For example, the BIOS first executes a power on self test (POST) and then load the operation system (OS). The BIOS also provides an interface that allows a variety of different parameters to be set. Particularly, the BIOS specifies clock and bus speeds and other parameters that affect performance of the computer system. The BIOS finally transfers control of the computer system to an operating system. The BIOS configurations are stored in a non-volatile memory (e.g., a non-volatile random-access memory (NVRAM)) or a read-only memory (ROM).
Various BIOS errors caused by user mistakes, power interruption during changing the BIOS, or virus infection can render a BIOS dysfunctional. As a computer cannot be booted without a functional BIOS, a corrupted BIOS can cause computer failures and damage system performance.